Vitamin D protects a number of important functions in the body. In addition to supporting healthy bones and muscles, it supports cardiovascular health and immune function. Although direct sunlight provides natural vitamin D, many individuals of all ages, especially the elderly, do not get enough vitamin D from sunlight and their diet. Vitamin D supplementation can be of great benefit in these situations. However, the powders used in many pre-mixed vitamin D dilutions frequently contain potentially detrimental ingredients such as lactose, as well as preservatives such as BHT, BHA, sodium benzoate, and sorbic acid. Thorne’s vitamin D is formulated for individuals who are sensitive to those ingredients.